I did receive an update. My increased for PTSD (30 to 50) and migraines (30 to 50) both went through, and between those and my other ratings I went from a combined 70 to a combined 80. The claim was kept open because they inferred TDIU and deferred the TDIU claim, and are awaiting my 21-8940. They also sent a second letter, which I received today, which contained a form to give to my previous employer.
For some background, I did not make a claim for TDIU because at the time I filed for my increase I had a combined 70% but no conditions at 40% or greater, which is a criteria for T